Pump sealing system



April 13, 1937. w. s. ROBINSON PUMP SEALING SYSTEM Filed June 11, 1955INVENTOR WALLACE SINCLAIR Roam/sou BY ML 6 NE Y5 Patented Apr. 13, 1937g 2,017,011 t V n PUMP SEALING s'Ys'rli i Wallace Sinclair,Robinsonyvancouverg British 2 I Columbia, Canada "Application June 11,1935, Serial No; 26,056 I t ioiaimflioi. 103;111)" My invention relatesto improvements in gland sealing methods and systems, which areparticularly. adapted for use on the glands of centrifugal pumps in oilrefineries and other places where volatile oils are pumped. a

The objects of the present invention are to provide means wherebyeconomy in packing material is effected; whereby the adjusting ofpacking glands at each operation of the pump is rendered unnecessary,and whereby the liquidpumped is definitely prevented from escapingoutwardly through the glands, thus preventing loss of liquid and dangerof fire or explosion. The invention consists essentially of providingthe gland of a pump with a port intermediate its length through whichwater is adapted to be admitted from a tank supported in a positionelevated above the pump, as will be more fully described in thefollowing specification and shown in the accompanying drawing,in.which:

The drawing is a general view of the invention part in section.

The numeral I indicates a pump having a driven shaft 2 journalled inbearings 3 of the pump casing 4, which is fitted with an impeller 5.

The shaft 2 is surrounded with glands 6 consisting of packing material Iand gland nuts 8. Intermediate the length of the packing l of each gland6 is a lantern gland 9 having radial openings in through its walls.

Mounted at a suitable height above the pump is a sealed tank ll having awater supply pipe I2 connected to it adjacent its bottom wall Thissupply pipe is fitted with two stop valves l3 be- 35, tween which afaucet I4 is placed, the purpose of which will hereinafter appear.

On the side of the tank II are pet cocks l5 disposed at desired heightsand also a water gauge I6 which is preferably provided at its upperextremity with a priming cook l1.

From anupper portion of the pump casing l a pipe I8 is extended upwardlypassing through the bottom wall of the tank and extending to a pointadjacent its upper extremity as at I9, this pipe is fitted with a valve20. i

A gravity discharge pipe 2| extends downwardly from the base of the tankI I, branching oif as at 22 to each of the bearings 3 wherethey'communicate with ports 23 disposed to register with the position ofthe lantern glands 9. For convenience in replacing packing and otherrepair work the branches 22 are each provided with valves 24. The pipei8 is at least as large as, if not larger than, the discharge pipe 2|.

The operation of the system in pumping a liquid such as naphtha is asfollows:-. A

' Water is admitted to the tank H through the valves 13 of the supplypipe 12 until it reaches the level of the uppermost pet cock I5, thevalves 24 on the branches 22 of the pipe 2| are opened to allow thewater to flow around and through the lantern glands-9 and into theglands 6 where the packing material becomes to some extent impregnatedwith water keeping it soft and pliable,

yet sufliciently tight on a relativelyslack adjustment to keep theglands sealed. Where packing suitable for naphtha and gasoline is used,gland nut adjustment is required each time the pump is started andstopped and the force used in compressing the packing material to renderthe gland reasonably tight causes heat in the bearings and sets up agaseous and liquid leak which is very dangerous especially when itoccurs in the proximity of electric motors.

When the pump is set in motion the pressure of water at the lanternglands 9 will be equal to that developed in the pump casing plus thehead of water in the tank and its pipe connections above the glands, andalso plus the dliference in specific gravity between the water and anynaphtha in the pipe l8, so that any leakage past the glands will besatisfied with water flowing from the ports 23 to the pump casing andfrom the ports 23 outwardly through the gland nuts 8; the naphtha beingunder lesser pressure than the water will be unable to flow outwardsfrom the pump casing, hence, no loss of naphtha will occur and no fireor explosion hazard will develop. As water leaks past the glands 6 fromthe tank so naphtha is forced up into the tank through the pipe l8 tokeep said tank full. Thedifference in specific gravity of the twoliquids will leave the naphtha on the top of the water and if a fewspots of liquid of a specific gravity in between that of water andnaphtha are introduced into the gauge glass Hi the water level in thetank can be readily determined at all times.

A surplus of naphtha can be ejected from the tank H by admitting waterthereto under suitable pressure from the pipe l2, or, if the pump isstopped, by first draining off the water and then the naphtha throughthe faucet I4 or alternately from the pet cocks l 5.

Water may be supplied to the tank through pipe l2 to compensate for theloss of water leaking past the glands B. The method of regulating theflow of water to the tank is as follows:

'after determining the amount of water leaking past the glands within acertain period of time,

the valves it are closed and the faucet I4 is opened. Then the valve I3farthestaway from the tank is opened suiilciently to allow the water todrip from the faucet H at the same rate as 6 the water drips from theglands. When the water is flowing at the desired rate, the faucet isclosed and the valve adjacent the tank is opened, allowing the water toflow into the tank. In this way the apparatus will function 10 for hourswithout any attention and there is no danger of the water pressurebecoming reduced or of naphtha getting into the glands and leaking pastthem.

In order to ensure the pressure of the water at 15 the glands beingequal to that developed in the pump casing plus the head of water in thetank, the pipe 18 is at least as largeas the pipe 2|. If it were not aslarge as the pipe 2| a good deal of 20 the pressure developed in thepump casing would be lost due to the fact that the water would beflowing away from the tank faster than the liquid would be suppliedthereto through pipe l8.

If desired a relief valve could be used in the top of the tank I I toadmit air thereto. in which case the pipe l8 could be dispensed with.

What I claim as my invention is:

Apparatus for sealing the glands of a centrifugal pump against leakagethrough said glands of the liquid pumped comprising packing looselypacked about the shaft of the pump in the bearings, a sealed tankdisposed above the pump. means for continuously supplying a sealingfluid to the tank, a pipe communicating with the easing of the pump andextending into the tank and terminating adjacent the top thereof fordelivering some of the liquid pumped directly ontothe top of the sealingfluid under the discharge pressure of the pump, a discharge pipe fordelivering sealing fluid from the tank to the packing in the glandsunder pressure greater than that developed in the pump, said sealingfluid being adapted to circulate through and out of the packing, andmeans through which the flow of the sealing fluid to the tank may beregulated substantially to compensate for the leakage of sealing fluidout of the glands. 1

WALLACE SINCLAIR ROBINSON

